Simultaneous engineering of the interface and bulk layer of Al/sol-NiO sub(x)/Si structured resistive random access memory devices

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2014-07, Vol.2 (30), p.6148-6154
• Main Authors: Yoon, Doo Hyun, Tak, Young Jun, Park, Sung Pyo, Jung, Joohye, Lee, Heesoo, Kim, Hyun Jae
• Format: Article
• Language: English
• Subjects: Aluminum; Annealing; Density; Devices; Electrodes; Interlayers; Oxides; Silicon
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/c4tc00858h

In our previous work, the pristine sol-NiO sub(x)/S i based device did not exhibit reproducible resistive switching due to the presence of native interlayer oxide. To solve this problem, we investigated high-pressure hydrogen gas annealing at a stack of Al/sol-NiO sub(x)/Si to engineer the interface and bulk layer simultaneously. Different from the pure nitrogen high-pressure gas annealing which only affects the bulk properties of the system, we found that the high-pressure hydrogen gas can alter both the interfaces and bulk layers. As a result, the native interlayer oxide thickness at the NiO sub(x)/Si interface was reduced and the overall density of oxygen vacancies was increased due to the reduction of atomic hydrogen. Consequently, a good condition for less randomized generation of conducting pathways was secured which led to improved stability of high- and low-resistance states, as well as a larger ratio of high and low resistances regardless of a high free energy of formation at the bottom electrode (Si).